Why do my forms keep jamming in the printer?

Why do my forms not re-fold properly?

Why do I get shocked when touching the paper?

What are the common problems in sheeted laser printing?

What are the common folding problems in continuous laser printing?

What are the common problems found in forms in a reel?

Why do my forms keep jamming in the printer?

There are many factors which may cause the forms to jam in your dot-matrix printer. However, try to rule out any issues with the printer itself before looking at the paper as the culprit. From our experience, minor adjustments with the printer can fix jamming problems. Here is a checklist of what you can do:

1) Adjust the paper thickness setting of the printer.

This is the most neglected process often assumed that no adjustment is necessary when feeding 2ply as compared with a 5ply continuous forms. This also results in poor image on the succeeding multipart form, as the impact is weaker due to the incorrect setting for the forms. Below is a guide on the recommended position:

Paper Type	Lever Position *for 9-pin Epson LX-300+ model
Plain paper (single sheet or continuous forms)	0
Carbonless multipart forms with: 2 sheets (original + 1 copy) 3 sheets (original + 2 copies) 4 sheets (original + 3 copies) 5 sheets (original + 4 copies)	0 1 2 3

*Other models may have different lever positions for different multi-part forms. Please consult your manual for the correct settings.

2) Unbundle the forms out of its packaging box.

Leaving the forms inside the box when printing can cause the forms to skid on the sides of the box resulting in uneven feeding and ultimately jamming. Thick paper, such as multi-part forms requires a straight paper path. Freeing the forms from its box and packaging will make sure that there are no obstructions when printing.

3) Align both sides of the tractor feeder.

Make sure to align BOTH pull tractor feeders into the CENTER of sprocket holes of the continuous forms. If the pull tractors are misaligned and positioned on the left or right of the sprocket holes and not in the center, it may cause the paper to feed improperly, jam or tear easily.

4) Raise the paper guide.

When using side crimped multi-part forms, the copies may not align with the original. It his happens, raise the paper guide as shown. Otherwise, the paper may jam.

5) Use recommended multipart forms only.

Use only multipart forms that are joined by spot gluing or side-crimping, and that are free of wrinkles and waves. Never load multipart forms joined by metal staples.
Be sure the multipart forms does not exceed 0.015 inch (0.39mm) in thickness.

Why do my forms not re-fold properly?

The most common problems in impact printing relate to the re-folding of the printed forms. Folding properties are mainly determined by paper characteristics (thickness of paper) and the fold perforation (cut:tie ratio).

Single part forms for impact printers are particularly sensitive to low stiffness caused by thin paper. To avoid folding problems, make sure that the paper has a thickness of not less than 48gsm.

Multi-part forms normally fold without any problems, provided that the different paper parts have the same moisture content. Otherwise some of the parts can shrink/swell, creating folding problems.

It also goes without saying to follow the original folding pattern of the forms. If the original folding is not followed it will cause the forms to go against its perforation and result in dispersing of the forms.

Why do I get shocked when touching the paper?

Working with computer print-outs, you are probably all too familiar with the problems of static electricity: forms not folding properly, paper sticking together, all of which create problems in printers as well as in the post-processing equipment. The problem is either caused by too dry paper or by too dry air in the print room combined with too high paper resistivity. The risk of static electricity is also higher during colder weather, due to the lower relative humidity inside buildings. Another possibility, especially with high-speed printers, is that the printer is not properly grounded. Make sure that the machine is connected to a properly grounded connection on the soil or ground.

What are the common problems in sheeted laser printing?

WAVY EDGES

The problem of wavy edges occurs when the paper edges expand, while the centre retains its original dimensions. This tends to happen when the paper is exposed to air with a high relative humidity. It may also occur if cold paper is brought into a warmer room directly from an uncontrolled storage room. In both cases, moisture may condense on the cold paper, which in turn, makes the fibers swell.

TIGHT EDGES

Tight edges are caused by exposure to a dry atmosphere. Moisture nearest to the edges of the paper is released, making the edges shrink while the center of the paper maintains its original dimensions.

CURL

Curl can develop when sheeted paper is left unwrapped and exposed to dry air or as a result of uneven built-in tension in the sheet. The curl can also develop when the paper undergoes a significant rise in temperature in laser printer or copiers.

All three problems described above will cause feeding problems in printers and/or paper handling equipment.

What are the common folding problems in continuous laser printing?

LEANING STACKS

Leaning stacks occur if the cross perforations are not at right angles to the paper edge after printing. The deviation need only be as small as 0.1 degrees to result in a leaning of the stack of 30 degrees. The paper properties in the cross direction of the paper web are essential to obtain straight stacks.

U-SHAPED STACKS

If the cross perforation of the re-folded stack are built up too quickly, this will result in a U-shaped stack. This causes the stack to taper off at the top, so that the machine-parts which push the cross-perforations down cannot reach the paper. This causes a jam and the printer will stop. Experience has shown that this is mainly caused by a combination of perforation and paper.

To avoid jamming the perforation knives must be very sharp. Sharp knives give a clean cut, whilst blunt knives push fibers with it to the back of the paper. We usually recommend a cross-perforation pattern of 1mm: 4mm tie cut. This patter will minimize the U-shaped stack.

The storage time of the forms in their boxes and their conditioning are also important factors that influence the U-shape and consequently the runnability in the printer. We recommend that the converted forms should be stored for a week before using in order to avoid problems when re-folding.

What are the common problems found in forms in a reel?

If the forms are delivered in reels, one has to take into consideration that the perforations must not burst when the paper is being reeled up after the printing operation. The reeling up must be sufficiently tight so as not to cause a conical reel.

The tension of the web must not of course exceed the tension of the cross perforations, or they will break. The tensile strength of unfolded cross perforations is approximately 30% greater than in the folded version. Meaning cross perforation in forms delivered in reels is 30% stronger than in forms delivered folded in a box.

Significant weight is added when producing jumbo-sized reels such 50” diameter as opposed to the standard 40” diameter commonly available in Asia. High-speed printers without the proper unwind unit may find that the added size and weight causes the printer to slow down and have a hard time reeling in the jumbo rolls. Forcing the printer to reel in the added weight can cause the printer to break down and may also cause jamming. Make sure to consult with your manufacturer to have an unwind unit with a minimum unwind diameter of 50”. Anything below this specification is not recommended.